1. Field of the Invention
The present invention relates to an electrically operated mirror control device and a method of controlling the device in a reverse linking operation, and more specifically, relates to the electrically operated mirror control device which carries out the reverse linking operation of automatically tilting a mirror in reversing a vehicle and the method of controlling the device in the reverse linking operation.
2. Description of the Related Art
Rearview mirror devices, such as an automobile outer door mirror and a fender mirror, capable of changing a mirror angle in an upward/downward direction and in a rightward/leftward direction by running a DC motor (direct current motor) are known. The DC motor is rotated for a mirror surface control during a switch operation for controlling the mirror in a vehicle.
A mirror of the rearview mirror device can be tilt in every direction on a central fulcrum installed at a back of the rearview mirror device. By rotatably advancing or moving back a center of a pivot in any one direction of the right/left of the central fulcrum and in any one direction of the up/down of the central fulcrum, the angle of the mirror can be changed in a rightward/leftward direction and in an upward/downward direction respectively, and the mirror can finally be directed to a direction which is set based on the angles of the rightward/leftward direction and the upward/downward direction.
The centers of the pivots for the rightward/leftward direction and the upward/downward direction can rotatably be advanced and moved back by operating respective individual DC motors, and the angle of the mirror can be adjusted in a direction which is determined by the individual DC motor driven by a switch operation.
Apart from the adjustment of the mirror surface angle by the switch operation mentioned above, an outer door mirror comprises a mechanism of changing angles, wherein, when a shift position of a transmission of a vehicle is placed in a reverse gear position, a mirror is automatically turned downward at a predetermined angle set in advance, and wherein, when the shift position of the transmission is shifted from the reverse gear position to another gear position, for example, a drive gear position, the mirror is automatically turned upward and returned to an original angle.
Accordingly, when the vehicle is backed up into a garage, a reverse linking operation is carried out, wherein the mirror is tilted downward in reversing a vehicle, and wherein the mirror is automatically returned to the original angle except during reversing of the vehicle. It is preferable that the rearview mirror device allows a driver to check the vicinity of rear wheels at a slightly downward angle, rather than the right behind the vehicle, because rear wheels that turn into a blind spot can be visually checked.
In the tilting operation of the outer door mirror in reversing the vehicle, the mirror is tilted at a predetermined mirror surface angle in reversing the vehicle, in some case, an angle desired by a driver is different from the predetermined mirror surface angle. Regarding an improved automobile rearview mirror device which automatically turns the mirror downward in reversing a vehicle, JP2003-267137A discloses a technology of changing angles, wherein, when an mirror surface angle operated by the driver in reversing a vehicle is stored, and the mirror is turned downward in reversing the vehicle again, the mirror is turned downward at the mirror surface angle stored previously.
However, in the technology disclosed by JP2003-267137A, the mirror surface angle is changed every time the mirror of the rearview mirror device is adjusted in reversing the vehicle. Therefore, when the driver changes angles, the mirror surface angle is frequently required to be readjusted.